The soul who refuses to go to Earth in Soul is 22.
22 is a cynical, quick-witted new soul who has spent an extremely long time in the Great Before, the fantastical realm where souls develop personalities and interests before being sent to Earth. Tina Fey provides 22’s voice in the film.
Unlike most new souls, 22 has no desire to become human. She is resistant to the idea of life on Earth and has repeatedly failed to discover a “spark,” the quality needed to earn an Earth Pass. The Jerrys assign Joe Gardner to mentor her, hoping he can help her complete the process.
Viewers sometimes confuse 22 with Jerry or Terry, but those names belong to beings associated with the Great Before and the afterlife’s administration. Joe is the human jazz pianist who becomes her mentor, not the soul refusing Earth. The companion short 22 vs. Earth expands on the character’s earlier rebellion and was created specifically to explain why she resisted leaving the Great Before.